In addition to the routine transient clinical applications of denture adhesives and ostomy devices, there exist psychological needs that require confidence and security during long uninterrupted periods of use or during use under stressful conditions.
While many bioadhesives suitable for attachment of ostomy devices and dentures to mucous membranes are known in the art, the duration of their adhesive properties are relatively short so that frequent replacement of the adhesive is necessary. More specifically, after a few hours of use, a denture adhesive agent interacts with saliva to such a degree that the adhesion force is reduced below 0.3 pounds/inch which is below the limit of failure. Accordingly, much research has been directed to finding a bioadhesive which at least equals the initial holding power of commercially available materials and also has an extended adhesive life of more than 12 hours. Various compounds such as sodium, calcium and magnesium salts of lower alkylvinylether-maleic acid copolymers have been added to bioadhesive formulations to improve strength and durability as disclosed in U.S. Pat. Nos. 3,008,988; 3,736,274; 3,833,518; 3,868,339; 4,183,914; 4,217,342 and 4,217,343. Recently zinc and strontium unmixed salts of lower alkylvinylether-maleic acid copolymers have been developed for this purpose as taught in U.S. Pat. No. 4,758,630. However, these partial salts are effective for considerably less duration than desired, usually functioning not more than a few hours when subjected to stressful use. Accordingly, it is an object of this invention to produce a bioadhesive whose holding power is extended for significantly longer periods of time.
Another object of the invention is to produce an economical and commercially acceptable composition having a long shelf life and high adhesion power.
Another object of the invention is to provide a method of using the improved bioadhesive as a denture fixative.
Still another object is to provide a method of manufacturing a bioadhesive composition.
These and other objects of the invention will become apparent from the following description and disclosure.